The Long-Range Characteristics of Drought and Flood Evolvement in the Mid-Line Area of Water Transfer from South to North China
南水北调中线地区旱涝变化的长期特征

By use of data 526 years, the methods of synoptics, climatology and statistics have been investigated for the characteristics of drought and flood that over North China and the Hanshui River valley, and the drought index computed also. The long-range evolvement of regional drought and flood distribution, and the requirement of water resources along the mid-line Water Transfer from South to North China were given.